This disclosure relates to vibratory conveyors used for delivering an adjustable and controlled flow rate of a stream of bulk product or consumable particulates. More particularly, this disclosure is directed to measurement of the displacement and speed of the vibrating bulk product as it is fed along the path of the vibratory conveyors.
Vibratory conveyors are recognized, especially as a raw materials unit operation, for minimizing wasted energy, as well as reducing wastes and by-products. It is often desirable to use vibratory conveyors that employ, for example, aluminum or stainless steel pans, trays, chutes, and troughs, as opposed to endless streams of unsanitary conveyor belts for dispersing and weighing unpackaged, bulk-fed foodstuffs. In such an apparatus, there is no conveyor in the usual sense. Rather, a pan, tray, chute or trough is imparted oscillatory motions of small amplitude so that the apparatus stays substantially in one place as foodstuffs and the like, lying thereon are urged to move in continuous flow, typically for dispensation.
Since it is not required to provide for recirculation as is typically required for a conveyor, the pan, tray, chute or trough of the vibratory conveyor may be monolithically, smoothly, and rigidly formed and constructed from, for example, fluoropolymer resins and stainless steel, which may be especially adapted to be easily cleaned and maintain cleanliness. The pan, tray, chute or trough may also be especially adapted for easy removal from the device for such cleaning. The surface of the pan, tray, chute or trough may be coated with an antimicrobial material, as well.
Nonetheless, measuring the weight of the product while using a vibratory conveyor apparatus is a problem recognized within the food manufacturing and packaging industry. This is because the oscillatory motions of the dispenser deleteriously affect whatever weighing apparatus is being used. This is true both in the ability of the weighing apparatus to accurately measure the weight of the product being vibrated and conveyed and in the ability of the weighing apparatus to maintain reliability and longevity during such use.
A known type of vibratory weighing conveyor that overcomes the challenges associated with making an accurate measurement of weight during operation is the Magna Weigh Feeder® manufactured by Crescent Systems, Inc. in Tualatin, Oreg., USA. The Magna Weigh Feeder® is an in-line weighing conveyor designed to feed bulk product by weight. In essence, vibratory weighing conveyors, like the Magna Weigh Feeder®, combine the cleanliness of a vibratory conveyor with the weighing capabilities of a weigh belt. The bulk product conveyed and dispensed with the Magna Weigh Feeder® can accurately measure the product, without disrupting flow rate outputs. A vibratory weighing conveyor, like the Magna Weigh Feeder®, is well adapted for providing an adjustable flow rate.
Still, another problem recognized within industry regarding the use of vibratory conveyors and vibratory weighing conveyors like the Magna Weigh Feeder® is the measurement of speed or velocity of the product in motion. It is easy to measure speed on a belt conveyor because product speed is essentially the same as the belt speed. However, when using a vibratory conveyor or vibratory weighing conveyor, a recirculating belt does not exist and the product is in continuous state of travel, as well as vibration. Further complicating the issue, is that various products behave differently when subjected to vibration.
Accordingly, there is a need for a novel and improved vibratory conveyor or vibratory weighing conveyor that provides for measuring the speed of the product during operation.
The following patents are incorporated by reference herein in their entireties: U.S. Pat. No. 5,780,780 issued on Jul. 14, 1998 to the applicant and U.S. Pat. No. 8,710,379 issued on Apr. 29, 2014 to the applicant.